Pulley attachment for tractors



Nov. 9, 1937. c. E. FRUDDEN 2,098,492

PULLEY ATTACHMENT FOR TRACTORS Original Filed June 13, 1935II/////IIIIIIIIIIIIIIIIIII7///////i\ !III//II//////////////////IIIIIIIAPatented Nov. 9, 1937 UNITED STATES.

PATENT OFFICE PULLEY ATTACHMENT FOR TRACTORS Conrad E. Frudden,Wauwatosa, Wis., assignor to Allis-Chalmers Manufacturing Company,Milwaukee, Wis., a corporation ofDelaware 9 Claims.

The invention relates to pulley attachments for tractors, and it isconcerned more specifically with attachments of this kind in which bevelgears are used for transmitting rotary movement from a power drivenshaft to the pulley shaft. The present application is a division ofapplication Serial No. 26,352, filed June 13, 1935, by Conrad E. Fruddenand Walter F. Strehlow, for Motor vehicle.

Close tolerances, usually in the order of thousands of an inch, must bemaintained in the mounting of bevel gears, if they are to operate attheir best possible efficiency, as is well known. In poWer'take-ofiattachments for tractors, using bevel gears, it has heretofore been acommon practice to use shims in order to secure the bevel gears in theirclosely predetermined relative positions, but the use of shims was ahandicap in providing a readily demountable belt pulley attachment andone in which the bevel gears were to be disengaged in order todisconnect the pulley shaft from the power shaft.

It is an object of the invention to do away with the use of shims whereit is desired to ad just the depth of mesh of a pair of intermeshingbevel gears for best efiiciency. According to the preferred manner ofpracticing the invention one of the intermeshing bevel gears is securedto a shaft which is journaled in axially fixed position in a sleeve, andin order to adjust the depth of mesh of the bevel gear on the shaft withits mating gear the sleeve is moved either forwardly or backwardly inthe direction of its axis. There are an infinite number of axialpositions of the sleeve which afford different depths of mesh of thebevel gears, and into which positions the sleeve may be moved by eitherforward or backward movement in the direction of its axis but the sleeveis not to be locked voluntarily in any one of all these possible axialpositions. It is to be locked only in a definite number of predeterminedaxial positions which are spaced from. one another an amount which issuitable in making adjustment of the depth of mesh of the bevel gearsfor best eiiiciency, and which amount in the case ofsmall bevel gears,as in tractors, may be five thousandths of an inch in the direction ofthe sleeve axis. The locking of the sleeve in any one of suchpredetermined axial positions is accomplished according to the inventionby means of a locking mechanism which may be tightened to hold thesleeve positively in any selected one of said positions against rotaryas well as axial displacement and which, while being tightened, aids inlocating the Sleeve with.

great accuracy in the selected position. The individual axial positionsof the sleeve differ from one another only a comparatively small amount,in the order of thousandths of an inch, as stated, and it is necessaryto make sure that every time any one'of these positions is selected thesleeve takes that position with the highest accuracy. For instance, ifthe sleeve is first locked in a certain position, then unlocked andmoved to another position, and after that looked again in the positionin which it was locked first, it should when locked in said firstposition for the second time occupy precisely the same position which itoccupied when it was locked in that position the first time. Itis,therefore, another object of the inventionto provide a locking mechanismof the described character which does not lose its precision under theforces to which it is subjected during tightening and under the forceswhich are transmitted to the sleeve by the shaft which is journaled inthe sleeve.

Another object of the invention is to provide a bevel gear driven beltpulley attachment for tractors, which may readily be mounted on andremoved from a tractor andwhich after being mounted on the tractor maybe positively locked thereon by tightening of a Wedge connection, in anyone of a predetermined number of axial positions, each of such axialpositions affording a different depth of mesh of the bevel gears, andthe construction being such that the depth of mesh of the bevel gearsmay be adjusted for best efficiency by trying several positions of theattachment.

Another object of the invention is to provide a bevel gear driven beltpulley attachment which may readily be secured on a tractor in severalaccurately predetermined positions in which the bevel gears are in meshwith each other, and in a position in which the bevel gears are out ofmesh with each other.

Still another object of the invention is to provide a belt pulleyattachment which is simple and compact in construction, efiicient inoperation, and which may be manufactured at low costs;

These and other objects and advantages of the invention will be apparentfrom the following description. A clear conception of an embodiment ofthe invention and of the operation of a device constructed in accordancetherewith may be had by referring to the drawing accompanying andforming part of this specification.

Figure l is a sectional View through the atachment and through a portionof the tractor.

Figure 2 is a top view of the attachment, the

belt pulley being omitted from the pulley shaft in this view.

The tractor to which the attachment is secured comprises a clutchhousing I mounted between frame channels 2 and 3 by means of mountinglugs 4 and 5 and enclosing a power shaft 6 driven from the tractorengine. I indicates a belt pulley shaft which is rotatably mounted in asleeve 8 by means of a ball bearing 9 seated in the sleeve 8 at one endthereof and by means of a roller bearing III seated in the sleeve 8 atthe other end thereof. The outer race of the ball bearing 9 abutsagainst a shoulder of the sleeve 8 and is retained by a snap ring II,and the outer race of the roller bearing I I] is similarly securedwithin the sleeve 8. The inner race of the ball bearing 9 is axiallyretained on the shaft 1 by a shoulder and a snap ring I2, and the shaftis thus prevented from axial displacement within the sleeve 8; A bevelgear I3 is integrally formed with the shaft I and meshes with a bevelgear I4 keyed to the power shaft 6, and a belt pulley I5 is secured ,tothe outer end of the shaft I projecting from the sleeve 8. A suitabledust'seal, not shown, may be mounted in the outer end of the sleeve 8 atthe side of the roller bearing II] facing the hub of the belt pulley I5.The inner end of the sleeve 8 is slidingly fitted into a bore of aninternal web I6 of the clutch housing I, the diameteriof the borecorresponding within close limits to the outside diameter of the portionof the sleeve. 8 seated in the bore. An intermediate portion of thesleeve 8 is slidingly fitted into a bore of' the mounting lug 4 of theclutch housing I, the channel 2'having an aperture registering with thebore in'the lug 4. An oil seal I'Lpreferably in the form of a cork ring,is retained in a counter bore:of the lug lby the web of channel 2, andan internal flange l8 projects inwardly from the sleeve 8, wherebylubricant into which annular groove 20,.the holes I9 being isolated fromone another by circumferential portions of the sleeve extendingtherebetween and tapered to receive the tapered end of a set screw 2|which is screwed into a threaded hole of a wall portion of the clutchhousing I. ,The holes |9 are arranged on a helical: line around the axisof sleeve Band are. equally spaced from each other circumferentially ofthe sleeve, that is, if there are six holes in the sleeve, the holeswill'be angularly offsetsixty degrees relative to each other. As to' therelative spacing of the holes in the direction.

of the sleeve axis the showing of Figs. 1 and 2 is greatly exaggeratedin order to make the helical character of the arrangement of the holesreadily visible, but in actual construction the relative spacing of theholes in the direction of the sleeve axis is less than a small fractionof an inch, for

instance, about five thousandths of an inch. Fig. 2 shows two of theholes H! at opposite sides of the set screw 2|, one of the holes beingcloser to thegroove 20 and the other being farther from "the groove thanthe center of the se GI'GW By first loosening the lock nut 22 on the setscrew and then screwing the set screw back the tapered end of the setscrew may be withdrawn from the hole I9 in the sleeve in which it isshown in Fig. 1. The sleeve is then free to be rotated about its axisand also to be moved back or forth in the direction of its axis. Forpurposes of description it may be assumed that the sleeve is rotated ina direction so as to bring the hole I9 which in Fig. 2 is farthest fromthe groove 20, underneath the tapered end of the withdrawn set screw 2|,a rotation of the sleeve through an angle of sixty degrees beingnecessary for this purpose where the angular spacing of the holes issixty degrees as mentioned above. The set screw 2| may then be screweddown again and will enter the new hole I9 even if the center of the holewas not brought into perfect alinement with the center of the set screw,the tapered end of the set screw and the correspondingly tapered shapeof the hole l9 taking care of such slight inaccuracy in rotating thesleeve 8 by hand into the new position. As the set screw 2| is screweddown and tightly wedged into the new hole I9 the sleeve is againpositively fixed in position but the new position differs from theoriginal one in that the sleeve has been moved in the direction of itsaxis a very short distance farther into the clutch housing I, therelative axial spacing of the holes |9 being very short, as stated. Itwill be seen that due to the helical arrangement of the holes l9 aboutthe axis of the sleeve 8 the sleeve may be moved in or out relative tothe clutch housing in the described manner for very short but definitedistances, and an inexpensive, simple and efficient way of regulatingthe depth of meshof the bevel gears I3 and I4 without the use of shimsis therefore provided. In order to find the proper'axial position of thesleeve 8 in which the bevel gears I3 and I4 have their proper depth ofmesh for best efliciency,

which is indicated by the backlash: of the pulley shaft 1, it is usuallynecessary to try different holes I9 when the belt pulley unit is mountedin the tractor for the first time. After the proper position has beenfound an arrow 23 (Fig. 2) is stamped on the sleeve 8 opposite to anarrow 24 on the frame channel 2, alinement of the arrows indicating thera-ngular position of the sleeve in which the set screw 2| engages thehole I9 which has been found to afford the proper depth of mesh of thebevel gears. If it is desired to dis engage the bevel gears I3 and I4from each other so that the belt pulley may remain stationary while thepower shaft 5 revolves, the set screw 2| is withdrawn from the taperedhole in which it is shown in Fig. 1, whereupon. the sleeve 8 may bemoved outwardly by pulling on the belt pulley I5 until the groove 28registers with the withdrawn set screw 2|. The sleeve and bevel gear I3will then occupy the dash-dotted line position indicated inFig. 2, andthe sleeve will still be seatedin the bore of'the web I6, and byscrewing the set screw down into the groove 20 the sleeve will be heldin a position in which the bevel gears are out of mesh. In order tobring the bevel gears again in mesh with each other the operation isreversed, and by keeping'the arrow 23 of the sleeve during thisoperation in alinement with the arrow 24 of the frame channel 2 the holeI9 which affords the correct depth of mesh may readily be registeredwith the set screw 2 I. Generally speaking, the relative spacing of theholes I9 in the direction of the axis of the sleeve8 is a small fractionof the total depth of mesh of the bevel gears l3 and I4 while thespacing between the groove 20 and the hole I9 nearest thereto, in thedirection of the sleeve axis, is larger than the total depth of mesh ofthe bevel gears. If desired, the sleeve 8 with the shaft 1 journaledtherein,.together with the bevel gear I3 and the belt pulley l5, may beentirely withdrawn from the clutch housing, the maximum diameter of thebevel gear l3 being somewhat shorter than the diameters of the bores inthe web l6 and lug 4 so that the bevel gear I3 can pass therethrough.The opening in the channel 2 which registers with the bore in the lug 4may then be closed by a suitable cover. 7

It should be understood that it is not intended to limit the inventionto the exact details of construction herein shown and described, forvarious modifications within the scope of the claims may occur topersons skilled in the art.

It is claimed and desired to secure by Letters Patent:

1. In a motor vehicle, a housing, a rotary power shaft within saidhousing, a sleeve having a series of helically arranged tapered holes init and being mounted in said housing for rotary and longitudinal slidingmovement on an axis angularly disposed relative to the axis of saidpower shaft, a pulley shaft extending through said sleeve and rotatablymounted therein in axially fixed posi tion, bevel gears secured to saidpower shaft and pulley shaft for transmitting rotary movement from saidpower shaft to said pulley shaft, and a set screw on said housing havinga tapered end adapted to be wedged into any selected hole of said seriesfor positively locking said sleeve in a plurality of axially adjustedpositions affording slightly different depths of mesh of said bevelgears.

2. An adjustable mounting for bevel gears, comprising a support, asleeve element mounted on said support for rotary and axial movementrelative thereto and having more than two radial apertures thereinoffset against one another axially and circumferentially of said sleeveelement, a shaft rotatably mounted in said sleeve element in axiallyfixed position relative thereto, a bevel gear secured to said shaft atone end of said sleeve element, and a locking element mounted on saidsupport for adjustment radially of said sleeve element and having atapered portion adapted to wedgingly engage any one of said radialapertures for positively securing said sleeve element against axial androtary movement relative to said support, the distance between parallelplanes extending radially of said sleeve element through the centers ofthose of said apertures located respectively nearest to and farthestfrom said bevel gear being equal to a total range of axial adjustment ofsaid sleeve element desired for varying the depth of mesh of said bevelgea with a mating gear.

3. An adjustable mounting for bevel gears, comprising a support, asleeve element mounted on said support for rotary and axial movementrelative thereto and having more than two circular radially disposedapertures therein offset against one another axially andcircumferentially of said sleeve element, a shaft rotatably mounted insaid sleeve element in axially fixed position relative thereto, a bevelgear secured to said shaft at one end of said sleeve element, and alocking element mounted on said support for adjustment radially of saidsleeve element and having a conical portion adapted to wedgingly engageany one of said radial apertures for positively securing said sleeveelement against axial and rotary movement relative to said support, thedistance between parallel planes extending radially of said sleeveelement through the centers of those of said apertures locatedrespectively nearest to and farthest from said bevel gear being equal toa total range of axial adjustment of said sleeve element desired forvarying the depth of mesh of said bevel gear with a mating gear.

4. An adjustable mounting for bevel gears, comprising a support, asleeve element mounted on said support for rotary and axial movementrelative thereto and having more than two radially disposed apert-iuestherein offset against one another axially and circumferentially of saidsleeve element, each of said apertures being conical and taperingtowards the axis of said sleeve element, a shaft rotatably mounted insaid sleeve element in axially fixed position relative thereto, a bevelgear secured to said shaft at one end of said sleeve element, and alocking element mounted on said support for adjustment radially of saidsleeve element and having a conical end portion adapted to wedginglyengage any one of said conical apertures for positively securing saidsleeve element against axial and rotary movement relative to saidsupport, the distance between parallel planes extending radially of saidsleeve element through the centers of those of said apertures locatedrespectively nearest to and farthest from said bevel gear being equal toa total range of axial adjustment of said sleeve element desired forvarying the depth of mesh of said bevel gear with a mating gear.

5. An adjustable mounting for bevel gears, comprising a supportingmember, a sleeve member mounted on said supporting member for rotary andaxial movement relative thereto, one of said members having more thantwo apertures therein extending transversely to the axis of said sleevemember and being offset against one another axially andcircumferentially of said sleeve member, a locking element mounted onthe other of said members for adjustment radially of said sleeve memberand having a tapered portion adapted to wedgingly engage any one of saidapertures for positively securing said sleeve member against axial androtary movement relative to said supporting member, a shaft rotatablymounted in said sleeve member in axially fixed position relativethereto, and a bevel gear secured to said shaft, the distance betweenparallel planes extending radially of said sleeve member through thecenters of the two of said apertures which are farthest from each otheraxially of said sleeve member being equal to a total range of axialadjustment of said sleeve member desired for varying the depth of meshof said bevel gear with a mating gear.

6. A belt pulley attachment for motor vehicles, comprising a sleeveelement having more than two radial apertures therein offset against oneanother axially and circumferentially of said sleeve element, a shaftrotatably mounted in said sleeve element in axially fixed positionrelative thereto, and a bevel gear and a belt pulley secured to saidshaft at opposite ends of said sleeve element, the distance betweenparallel planes extending radially of said sleeve element through thecenters of those of said apertures located respectively nearest to andfarthest from said bevel gear being equal to a total range of axialadjustment of said sleeve element desired for varying the depth of meshof said bevel gear with a mating gear.

7; A belt pulley attachment for motor vehicles, comprising a sleeve.element having more than two radial apertures therein progressivelyofiset against one another axiallyand circumferentially'of saidzsleeveelement, ashaft rotatably mounted .in said sleeve element in axiallyfixed posi tion relative thereto, and a bevel gear-and a belt pulleysecured to said shaft at opposite ends of said sleeve element,thedistance between parallel planes extending radially of said sleeveelement'through the centers of those of said apertures located,respectively nearest to and farthest from said bevel gear being equal toa total range of axial adjustment of said sleeve element desired forvarying the depth of mesh of said bevel gear with a mating gear.

8. A belt pulley'attachment for motor vehicles, comprising a sleeveelement having morethan two radialapertures therein equally offsetagainst one another axially of said sleeve element, and equally spacedfrom one another circumferentially of said sleeve element,.saidapertures being isolated from one another by circumferential portions ofsaid sleeve element extending therebetween, a shaft rotatably mounted insaid sleeve element in axially fixed position relative thereto, and abevel gear and a belt pulley secured to said shaft at opposite ends ofsaid sleeve element, the distance between parallel planes ex- :tending;radially of said sleeve element through the centers of those of saidapertures located egooeme' respe'ctivelynearest to and farthest fromsaid beveligear' being equal to a, total range of axial adjustment ofsaid sleeve element desired for varying the depth of mesh of said bevelgear with a mating gear.

. 9; A belt pulley attachment for motor vehicles, comprising a sleeveelement having more than two radial apertures therein offset against oneanother axially and circumferentially of said sleeve element, a shaftrotatably mounted in said: sleeve element in axially fixed positionrelativefithereto and a bevel gear and a belt pulley secured" to saidshaft at opposite ends of said sleeve element, the distance betweenparallel planes extending radially of said sleeve element through thecenters of those of said apertures located respectively nearest to andfarthest from said bevel gear being equal to a total range of axialadjustment of saidsleeve element desired for varying the depth of meshof said bevel gear with a mating gear, said sleeve element also having acircumferential groove therein between said bevel. gear and said radialaperture nearest to the latter, and the distance between parallel planesextending ra'dially'of said sleeve element through the respectivecenters of said groove and nearest'aperture being not less than theamount of. axial adjustment of said sleeve element requiredgto bringsaid bevel gear out of mesh with said mating gear.

CONRAD E. FRUDDEN.

